1. Field of the Invention
The present invention relates to a combine-information processing apparatus, a method for processing combine-information, a program and a recording medium for detecting abnormal behaviors of manufacturing apparatuses using measured values of a plurality of items and other values.
2. Description of the Related Art
In conventional methods for analyzing a cause of quality degradation of products, a known method comprises: retrieving and collecting process data; calculating residual variables and distance variables through a principal component analysis; extracting a process variable, as a candidate cause of quality degradation, having a great contribution degree by calculating the contribution degree of each process variable to the residual variable that is out of an acceptable range and comparing the calculated contribution degrees, while extracting a score variable, as a candidate cause of quality degradation, having a great contribution degree by calculating the contribution degree of each score variable to the distance variable that is out of an acceptable range and comparing the calculated contribution degrees (see, e.g., Japanese unexamined patent publication No. 2003-114713 (p. 1, FIG. 1)).
The above-described method capable of analyzing the cause of quality degradation of products is deemed to be possible for detecting abnormal behaviors of manufacturing apparatuses which are the cause of quality degradation of the products.
However, the above method has a problem in detecting the manufacturing apparatus' abnormality since if the residual variable or the like, which is calculated from measured data obtained after adjustment of settings of the manufacturing apparatus within a basically adjustable range, is out of the acceptable range, the normal manufacturing apparatus is regarded as abnormal. For example, a normal manufacturing apparatus could be determined abnormal if its settings are improperly adjusted. Consequently, the conventional method that may misjudge the manufacturing apparatus' abnormality due to a simple error in adjusting the settings of the manufacturing apparatus has difficulties being used as a method for determining that the manufacturing apparatus is abnormal.